[FIX] html_editor: show header 1 name correctly in toolbar

[Mtaylorr]

Before this commit:

Selecting header 1 in the font dropdown will show header 1 display 1 which is wrong. They are 2 different fonts.

After this commit: Now every selected font show its corresponding name.

Added a test to check the flow for all possible fonts.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:

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